A. Field of the Invention
The present invention relates to pole-mounted lighting systems, and in particular, to means and methods for mounting on poles various structures related to elevated lighting fixtures for large area lighting.
B. Background of the Invention
There are many examples of pole-mounted large area lighting systems. They include sports field lighting; such as softball, baseball, football, soccer fields and the like. It also includes tennis court lighting, and playground lighting; and could also include such things as parking lot lighting.
The most conventional way of elevating lighting fixtures to enable large scale lighting is to install poles in the ground and then secure structures to the poles to facilitate such lighting. It is usually desirable to elevate the lighting fixtures as high as economically practical. The higher the light pole the costlier. Therefore there is usually a practical limit on the height of poles which is directly related to cost. Multiple fixtures normally are positioned on some sort of a cross-arm which is then secured to the pole. Multiple cross-arms on each pole are possible. Other structures, such as electrical boxes containing ballasts, circuit breakers, fuses, switches, and other electrical components are also commonly suspended along the length of the pole. Such components can either be associated with the cross-arms, or be spaced apart from and usually lower on the pole.
While it may appear to be elementary to accomplish lighting systems of this type, a number of different design criteria and considerations are involved. For example, it is not trivial to secure structures of substantial size and weight to a pole. The structures must be mounted securely and in a durable manner for long term use. The mounting structure must also be strong to support cross-arms, fixtures, and such things as ballast boxes; particularly in light of wind loads that exist on outdoors systems.
Another set of considerations involves cost of manufacturing and installation. As with most commercial goods, the cost of making the goods impacts significantly on the cost of the goods to consumers. There is normally high incentive to be able to present the lowest price to consumers; therefore there is high incentive to devise systems which are as inexpensive as possible to manufacture. This impacts on design and the type of materials utilized.
Another consideration is the shipping of these components from factory to installation site. Limits of size and weight come into play. For example, shipment via semi-trailer limits the maximum dimensions of pieces.
Still further, there is generally a high incentive to offer goods to consumers that are easy to install while meeting performance requirements for the types of components.
Still further, it is usually desirable that the goods be flexible and customizable to varying installation situations. In other words, it is most times advantageous to have, for example, mounting systems that are generally universal with the ability to work for different mounting situations such as, for example, different heights, diameter, and types of poles.
In the field of the present invention, these considerations apply. There are practical limitations on the number of light fixtures that can be suspended from each pole. It depends on factors such as the type of pole (examples are wood, steel, concrete), the height of the pole, and the lighting requirements associated with that pole. As a general rule it is most cost-effective to be able to elevate a maximum number of fixtures from each pole, as the poles and their installation comprise a significant amount of the cost for lighting systems.
In the same sense, because structures such as cross-arms, lighting fixtures, and ballast boxes are substantial in size, and need to be installed at elevated positions from the ground, it is highly desirable that the mounting procedures be as simple and quick as possible. With this is the need for flexible, almost universal, mounting components that can be adapted easily by the installers for different situations.
Many consumers also take into consideration how a certain system visually looks from an attractiveness standpoint, in cooperation with its functionality.
There are currently many ways of suspending lighting fixtures and related structures on poles for accommodating large scale lighting. It is submitted, however, that there is room for improvement in this field of art. Two specific examples are set forth below.
As previously mentioned, it is highly desirable to suspend as many lighting fixtures per pole as possible, in most situations. Currently a conventional way to attach fixtures to a pole is to mount one or more cross-arms to the pole, each cross-arm bearing multiple light fixtures and having separate pole-attaching hardware. One time saver that exists in the art is to connect the light fixtures to the cross-arm before raising the entire cross-arm assembly to its position at the top of the pole. However, if more than one bar of lights is required, significant time and effort must be utilized to position and then secure the first cross-arm, then the second, then any others.
Another example involves ballast boxes. They are normally secured by brackets that surround the pole and connect to the top and bottom of the ballast box. However, when installing and cinching the box against the pole, certain problems can exist. There are times when rotational or other forces can deform or even permanently warp the ballast box. This can significantly affect the ballast box in, for example, causing misalignment of any door on the box so that it does not fit securely, which in turn can lead to water leakage or other detrimental and potentially serious problems for the lighting system. For example, if the ballast box is not accurately aligned along the pole, when tightened, deformation or warping can occur. Another instance is if the pole is crooked. A still further example involves cases where wood poles are used and mounting brackets sink into the wood at different rates. Knots or other discontinuities in poles can also cause problems. It is to be understood that other situations can also cause problems resulting in the risk of deformation or warpage.
It is therefore the primary object of the present invention to provide a pole-mounted lighting system which improves over some of the problems and deficiencies in the art.
another object of the present invention is to provide a pole-mounted lighting system which securely and durably mounts structures to poles, but limits potentially damaging stresses on the structures when being mounted.
Another object of the present invention is to provide a pole-mounted lighting system which is easy to mount to the pole in a minimum amount of time and steps.
A still further object of the present invention is to provide a pole-mounted lighting system which is flexible in the types of structure and poles with which it can be used.
Another object of the present invention is to provide a pole-mounted lighting system which deters or avoids mounting problems related to misalignment of structures with respect to the poles, crooked poles, poles having surface irregularities, and poles such as wood poles which are crooked or have varying wood density, knots, or other discontinuities.
Another object of the present invention is to provide a pole-mounted lighting system which allows a significant amount of needed structure, for example, lighting fixtures, ballasts, or other electrical components, to be mounted on an existing pole.
another object of the present invention is to provide a light-mounted lighting system which allows for easy electrical interconnection of electrical components, even if they are spaced apart from one another on the pole.
These and other objects, features, and advantages of the present invention will become more apparent with reference to the accompanying specification and claims.